This article examines the structure, classification, cellular composition, and physiological functions of connective tissues in the human body. The study analyzes the characteristics of connective tissue proper, cartilage, bone, blood, and adipose tissue, emphasizing their roles in support, protection, transport, immunity, and tissue repair. The findings demonstrate that connective tissues possess diverse structural adaptations that enable them to perform specialized functions essential for maintaining physiological homeostasis. The clinical significance of connective tissue disorders and recent advances in regenerative medicine are also discussed.